News / Health

Researchers Discover the Biological Mechanism of Malaria Infection

Jessica Berman
Researchers say they have discovered how the malaria parasite gains a foothold inside the human body, causing the life-threatening illness.  The finding could lead to a new treatment for malaria - using a drug that’s already in clinical trials for use against another condition.

After taking a blood meal, experts say the malaria-infected female Anopheles mosquito injects about 1,000 parasites into the bloodstream.
 
The microorganisms quickly reproduce after each one enters a red blood cell, according Doron Greenbaum, a professor of pharmacology at the University of Pennsylvania.

“Each parasite divides from one into say 24 to 32 parasites in 48 hours.  So you can imagine that an initial thousand parasites can grow very fast,” Greenbaum said.

Greenbaum says he and his colleagues discovered that inside the red blood cells, the parasites utilize a series of proteins to reproduce. After sapping the cells of their nutrient machinery, the new-born parasites burst through the cell walls and back into the blood stream, where they infect new blood cells, producing millions more offspring.  After a one- to two-week incubation period, the parasitic infection causes the often fatal symptoms associated with malaria, including very high fevers, chills and sweats.

The discovery of this protein pathway inside the red cell could lead to the use of a new oral medication -- called sotrastaurin -- to treat the deadly infection. The malaria pathogen targets a particular enzyme called PKC, which weakens the the protein chain, dismantling the cells and causing them to collapse. But sotrastaurin blocks P. falciparum's interaction with PKC.

Without that interaction, Greenbaum says, the parasites can’t reproduce.

“They are sort of trapped inside the host cell and if they can’t get out, they can’t continue their lifecycle and within a couple of hours, they start to die,” Greenbaum said.

Researchers led by Greenbaum tested the experimental drug, now in clinical trials to prevent organ rejection in transplant patients, and the compound dramatically reduced the number of P. falciparum malaria parasites in infected laboratory mice.
 
Because sotrastaurin targets human cellular proteins, Greenbaum says P. falciparum can’t develop resistance to the drug which has made quinine and artemisinin drugs to treat malaria less effective in recent years.

An article by Doron Greenbaum and colleagues at John Hopkins University in Baltimore, Maryland describing how the malaria parasite reproduces itself is published in the journal Cell, Host and Microbe.

You May Like

UN: 1 Million Somalis at Risk of Hunger

Group warns region is in dire need of humanitarian aid, with at least 200,000 children under age of five acutely malnourished as drought hits southern, central part of nation More

Human Rights Groups Allege Supression of Freedoms in Thailand

Thailand’s military, police have suppressed release of independent report assessing human rights in kingdom during first 100 days of latest coup More

Jennifer Lawrence Contacts FBI After Nude Photos Hacked

'Silver Linings Playbook' actress' photos were posted on image-sharing forum 4chan; Federal Bureau of Investigations is looking into matter More

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Ukraine Schools Resume Classes, Donate to Government Forcesi
X
September 02, 2014 12:58 PM
A new school year has started in Ukraine but thousands of children in the war-torn east are unable to attend because of ongoing clashes with pro-Russia rebels. In Ukraine's capital, patriotic education has become the norm along with donations to support injured security forces fighting to take back rebel-held areas. VOA's Daniel Schearf reports from Kyiv.
Video

Video Ukraine Schools Resume Classes, Donate to Government Forces

A new school year has started in Ukraine but thousands of children in the war-torn east are unable to attend because of ongoing clashes with pro-Russia rebels. In Ukraine's capital, patriotic education has become the norm along with donations to support injured security forces fighting to take back rebel-held areas. VOA's Daniel Schearf reports from Kyiv.
Video

Video US Detainees Want Negotiators for Freedom in North Korea

The three U.S. detainees held in North Korea were permitted to speak with foreign media Monday. The government of Kim Jong Un restricted the topics of the questions, and the interviews in Pyongyang were limited to five minutes. Each of the men asked Washington to send a representative to Pyongyang to secure his release. VOA’s Carolyn Presutti has our story.
Video

Video Internet, Technology Offer New Tools for Journalists

The Internet and rapidly evolving technology is quickly changing how people receive news and how journalists deliver it. There are now more ways to tell a story than ever before. One school in Los Angeles is teaching the next generation of journalists with the help of a state-of-the-art newsroom. Elizabeth Lee has this report.
Video

Video Turkmen From Amerli Describe Survival of IS Siege

Over the past few weeks, hundreds of Shi'ite Turkmen have fled the town of Amerli seeking refuge in the northern city of Kirkuk. Despite recent military gains after U.S. airstrikes that were coordinated with Iraqi and Kurdish forces, the situation remains dire for Amerli’s residents. Sebastian Meyer went to Kirkuk for VOA to speak to those who managed to escape.
Video

Video West Africa Ebola Vaccine Trials Possible by Early 2015

A U.S. health agency is speeding up clinical trials of a possible vaccine against the deadly Ebola virus that so far has killed more than 1,500 people in West Africa. If successful, the next step would be a larger trial in countries where the outbreak is occurring. VOA's Carol Pearson has more.
Video

Video Survivors Commemorate 70th Anniversary of Nazi Liquidation of Jewish Ghetto

When the German Nazi army occupied the Polish city of Lodz in 1939, it marked the beginning of a long nightmare for the Jewish community that once made up one third of the population. Roughly 200,000 people were forced into the Lodz Ghetto. Less than 7,000 survived. As VOA’s Kane Farabaugh reports, some survivors gathered at the Union League Club in Chicago on the 70th anniversary of the liquidation of the Lodz Ghetto to remember those who suffered at the hands of the Nazi regime.
Video

Video Cost to Raise Child in US Continues to Rise

The cost of raising a child in the United States continues to rise. In its latest annual report, the U.S. Department of Agriculture says middle income families with a child born in 2013 can expect to spend more than $240,000 before that child turns 18. And sending that child to college more than doubles that amount. VOA’s Deborah Block visited with a couple with one child in Alexandria, Virginia, to learn if the report reflects their lifestyle.
Video

Video Chaotic Afghan Vote Recount Threatens Nation’s Future

Afghanistan’s troubled presidential election continues to be rocked by turmoil as an audit of the ballots drags on. The U.N. says the recount will not be completed before September 10. Observers say repeated disputes and delays are threatening the orderly transfer of power and could have dangerous consequences. VOA correspondent Meredith Buel reports.

AppleAndroid